Vehicles such as lawn mowers or off-road vehicles are equipped with a variable speed transmission for supplying engine power to driving wheels. Adjusting a shift position of the variable speed transmission varies the ground speed of the vehicle. In many cases, the shift position of the variable speed transmission is adjusted by a pedal system mounted on a vehicle floor. Typical examples of the pedal system are a seesaw pedal system and a dual pedal system.
An example of the seesaw pedal system disclosed in U.S. Pat. No. 5,263,385 includes a boss rotatable about an axis extending in a vehicle transverse direction, a front arm extending forward from one end of the boss, and a rear arm extending rearward from the other end of the boss. A further arm extends from the boss to be connected to a shift arm fixed to a transmission shaft of a variable transmission via a linkage. The front arm has a front depression surface, and the rear arm has a rear depression surface. While pressing down on the front depression surface increases forward-drive speed of the vehicle, pressing down on the rear depression surface increases reverse-drive speed of the vehicle. The front depression surface and the rear depression surface are spaced apart from each other in a vehicle front-rear direction.
An example of the dual pedal system disclosed in U.S. Pat. No. 6,237,711 includes a forward-drive pedal fixed to a forward-drive pedal shaft, and a reverse-drive pedal fixed to a reverse-drive pedal shaft, in which the forward-drive pedal and the reverse-drive pedal are arranged side by side in a vehicle transverse direction. The forward-drive pedal shaft and the reverse-drive pedal shaft are connected to a shift arm fixed to a transmission shaft of a variable speed transmission through a linkage.
The seesaw pedal system is simpler than the dual pedal system in construction, and thus is advantageous in terms of manufacturing cost. On the other hand, the dual pedal system is more complicated than the seesaw pedal system in construction, but is advantageous in that the sensations brought to the operator when depressing the forward-drive pedal and when depressing the reverse-drive pedal are substantially the same.